In many damp and warm environments, such as Southeast Asia regions, how to prevent foods or leather goods from being moldy is a common goal of a lot of people. At present a commonly adopted technique to meet this end is to place a chemical agent such as antiseptic, desiccant or deoxidizer into a container to curb or prevent growing of mildews. But used on foods the chemical agent could create ill effects to the health of human body. There is still room for improvement.
Nowadays there are patches and hanging cards absorbed with anti-mildew essential oil on the market. Please refer to FIG. 1, they generally are formed in a sheet structure including a base sheet 1, an upper sheet 2 and an essential oil absorption layer 3 sandwiched therebetween. The essential oil absorption layer 3 aims to absorb anti-mildew essential oil and has one side exposed to the air to evaporate the essential oil. Whether the essential oil is evaporated through the upper sheet 2 or base sheet 1 depends on the material thereof. However, the essential oil absorption layer 3 cannot hold a large amount of the essential oil; after used for a long period of time, the anti-mildew essential oil is almost evaporated to the end, thus replacement has to be done. Usability is lower. In the event that the anti-mildew essential oil is evaporated through the upper sheet 2 or base sheet 1, use duration is even shorter. There is also room for improvement.